FEATURES · §1.0

What Calyber does, with the inputs it does it from.

Every feature below is anchored to a real data point from a 13-week mesocycle run on Calyber. 1,068 sets, 26 exercises, 34 algorithmic adjustments, all traceable.

§01

Mesocycle Builder

Programs are configured per mesocycle: weeks, days per week, muscle priorities, and the RIR progression schedule. The builder generates a full week-by-week structure with planned exercises, set counts, rep ranges, and target RIR per session.

Methodology

Reference Data

Length
13 weeks
Days / week
5
Exercises
26
Total sets planned
1119

From Upper Body - 2026.

§02

Set-by-Set Logging

Logging is the input layer for everything downstream. Weight, reps, completion state, and exercise notes are recorded per set. Auto-progression suggests the next session's weight and rep targets based on prior performance.

e1RM formula

Reference Data

Sets logged
1,068
Sets skipped
51
Compliance
95%
Weeks logged
13 / 13

From Upper Body - 2026. Every set is the input the algorithm reasons from.

§03

Autoregulation Engine

After every session, the algorithm reads soreness, pump, workload, and performance signals and adjusts the next week's volume target per muscle group. Increments, decrements, holds: each is a documented response to a documented input.

AUTOREGULATION EVENT LOG · 34 EVENTS

Algorithm interventions across 13 weeks of Upper Body - 2026

WkMuscleΔ setsNew target
W6Biceps-111 sets · MEV 6 / MRV 16
W6Core/Abs-16 sets · MEV 6 / MRV 14
W6Shoulders+124 sets · MEV 10 / MRV 26
W6Triceps+114 sets · MEV 8 / MRV 18
W7Chest-113 sets · MEV 0 / MRV 0
W7Core/Abs-14 sets · MEV 0 / MRV 0
§04

Fatigue Map · MGFI

The Muscle Group Fatigue Index is a composite of soreness, pump, workload, and performance signals, split into a Readiness Index (RI, short-window) and an Accumulation Index (AI, decayed multi-session burden). The fatigue map renders per-muscle state so you can see which groups are fresh, building, elevated, or critical before stepping under the bar.

Fatigue Index reference

Reference Data

Composite inputs
4 signals
Decomposition
RI + AI
Update frequency
Per session
Muscle groups tracked
All trained

See /algorithm/fatigue-index for the full formula.

§05

Recovery Protocols

Triggered deload weeks based on MGFI thresholds. Per-exercise adjustments when a single movement spikes fatigue. Half-week and whole-session recovery commands when subjective inputs exceed sustainable ranges. The recovery system runs alongside the prescription engine, not as a manual override.

Methodology

Reference Data

Planned deload weeks
W13
RIR @ deload
Target ≥ 4
Trigger basis
MGFI threshold
Adjustment scopes
Per-exercise · half-week · session

Deload is a load reduction, not a rest week. Volume drops; movement continues.

§06

Per-Mesocycle Analytics

Block-level analytics for every completed mesocycle: e1RM trajectory per lift, weekly volume vs MEV / MAV / MRV landmarks, autoregulation event log, fatigue arc. The mesocycle is the clinical trial; analytics is the result.

E1RM TRAJECTORY · BENCH PRESS

Upper Body - 2026 · 11 weeks · Δ +32%

W3: 95W12: 125

Baseline W3: 95 lbs · Peak W12: 125 lbs · Δ +32%

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Begin your own mesocycle.

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Trial starts when you build your first mesocycle

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